Coronavirus FAQs: Do Masks Help? Is The Disease Really So Mysterious?

People wear face masks as they wait at Hankou Railway Station earlier this week in Wuhan, China. Experts say there is little evidence that masks prevent infection.

Xiaolu Chu
/ Getty Images

Originally published on January 25, 2020 4:14 pm

Many reports refer to the newly identified coronavirus in Wuhan, China, as a "mystery" virus. Is it really a mystery? Do masks help keep you from getting infected? If an animal carries the virus, will cooking it make it safe to consume?

These are some of the questions circulating about the virus called 2019-nCoV. Here are some answers.

Will a mask protect me?

There's a run on masks in China, with the belief that wearing one in public will protect an individual from exposure to droplets sneezed or coughed out by someone infected with the Wuhan virus.

But there's little evidence to suggest that the face masks worn by members of the public prevent people from being infected by breathing in the virus, says William Schaffner, a professor in the division of infectious diseases at Vanderbilt University Medical Center. "There really are no good, solid, reliable data."

According to the CDC, the kind of flimsy masks that people often buy in pharmacies may not tightly fit the face, so the wearer can still breathe in air — and infected droplets.

Stanley Perlman, a professor at the University of Iowa who studies coronaviruses, agrees that the mask won't necessarily prevent infection. But they do have some value, he says: Wearing a mask may stop an individual from directly touching their mouth and nose, which is a common way that viruses and germs enter the body. Masks provide some protection this way, he adds. "But what we teach is that they're not very good."

To protect themselves from infection, health care workers don't wear the kind of thin, over-the-mouth masks you see in operating rooms, which are designed to keep germs from leaving the mouths and noses of medical staff in the room. When it comes to preventing infection from their surroundings, health care workers wear N95 respirators, which fit much more tightly, says Schaffner. These respirators haven't been tested for effectiveness when worn by the general public, so there's no evidence to support a general recommendation, he says.

But there is one thing that experts endorse as a preventive: "Hand hygiene is the answer," Schaffner says, suggesting soap and water, since the abrasiveness of soap helps remove infectious particles from the hands. Centers for Disease Control and Prevention recommends scrubbing your hands for at least 20 seconds. Make sure to clean the backs of your hands, between your fingers and under your nails, advises the CDC. And scrub for 20 seconds — about as long as it takes to sing, at a moderate pace, the alphabet song.

Is this virus mysterious?

Judging by headlines, it is. Many media outlets refer to the Wuhan virus as "China's mystery virus."

"It was mysterious when we didn't know what it was," says Perlman. But once it was identified as a member of the family of coronaviruses, it was no longer so mysterious, he says.

Indeed, the Wuhan coronavirus appears to behave in ways that are similar to other coronaviruses like SARS and MERS. Health officials believe that like these two well-known coronaviruses, the Wuhan virus can be passed from person to person via exchange of fluids from the respiratory tract, although they still don't know precisely how.

While it's no longer such a mystery, there are still open questions about the Wuhan virus. We don't know how long it takes after exposure to get sick or which animal was the original source of the virus. "Each one of the rogue viruses that jumped species from animals to humans has its own characteristics," says Schaffner.

Any method of cooking will work, says Schaffner. "It's heat. The mode of delivering the heat doesn't matter," he adds.

So how are people infected by an animal that harbors the virus? "It's in the preparation that there might be some risk," says Schaffner. Handling raw before cooking presents a risk.

And at the market in Wuhan, where some people seemed to have become infected, live animals are sold and slaughtered. It isn't clear exactly how the virus spread from animals to people, but when an infected animal is killed and then skinned, small pieces of tissue or droplets of blood could spread into the air and transmit the virus, Schaffner says.

How worried should people outside of China be?

The general public should not worry at this time, says Schaffner. "There's an outbreak of coronavirus anxiety. I think we all ought to take a deep breath and step back," he adds. Compared to the flu cases seen each winter, he predicts that the Wuhan virus will be "a tiny little blip on the horizon."

"In terms of mortality rate, we're on the lower spectrum, which gives me some room for optimism," says Kevin Olival, vice president for research at the EcoHealth Alliance, who specializes in emerging infectious diseases

As doctors and officials learn more about the spread and scale of the virus, it will become more clear whether the virus poses any significant concern to Americans.

Do you have any questions about the Wuhan coronavirus outbreak? Email them to us with the subject line "Wuhan coronavirus FAQ" to goatsandsoda@npr.org and we may answer them in a story for NPR next week.